I suck at value estimates, but I would say around 50 USD. Probably more if you ebay it. To get rough estimates, just search ebay for the product you are selling and select show closed auctions or something and it will say how much that same thing has sold for in the past. Good for a rough estimate.

I would say roughly between $25 and $50. Most of your money is probly gonna come from the DS games. A few years back, my bro sold his N64 in perfect condition w/ 2 controllers and only got $11. Id like to add that you should try ebay or trade everything for store credit. Youll definitely get more bang for your buck.